Re: [PATCH] thunderbolt: icm: Remove Apple check for Alpine Ridge

From: Kai-Heng Feng
Date: Mon Aug 07 2017 - 02:50:56 EST


On Mon, Aug 7, 2017 at 12:49 PM, Kai-Heng Feng
<kai.heng.feng@xxxxxxxxxxxxx> wrote:
> In icm_ar_is_supported(), icm->upstream_port will be uninitialized if
> the hardware is not an Apple one.
>
> The uninitialized icm->upstream_port will later be dereferenced in
> pcie2cio_write(), causes a NULL pointer dereference issue.
>
> Commit f67cf491175a ("thunderbolt: Add support for Internal Connection
> Manager (ICM)") states that all Alpine Ridge will use ICM, so I guess
> it's safe to remove the Apple check.
>
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
> ---
> drivers/thunderbolt/icm.c | 7 -------
> 1 file changed, 7 deletions(-)
>
> diff --git a/drivers/thunderbolt/icm.c b/drivers/thunderbolt/icm.c
> index bdaac1ff00a5..2ab25aac5446 100644
> --- a/drivers/thunderbolt/icm.c
> +++ b/drivers/thunderbolt/icm.c
> @@ -514,13 +514,6 @@ static bool icm_ar_is_supported(struct tb *tb)
> struct icm *icm = tb_priv(tb);
>
> /*
> - * Starting from Alpine Ridge we can use ICM on Apple machines
> - * as well. We just need to reset and re-enable it first.
> - */
> - if (!is_apple())
> - return true;
> -
> - /*
> * Find the upstream PCIe port in case we need to do reset
> * through its vendor specific registers.
> */
> --
> 2.13.4
>

Forgot to CC LKML...